Process of treating cracked hydrocarbons



Sept. 20, 1932. T. T. GRAY 1,878,580

PROCESS OF TREATING CRACKED HYDROCARBONS Filed Jan. 10. 1927FRACT/O/VATO/P avwcnfo:

Patented Sept. 20, 1932 UNITED sr'ras PATENT OFFI THOMAS T. GRAY, OFELIZABETH, NEW JERSEY, ASSIGNOR TO THE GRAY PROCESSES CORPORATION, OFNEWARK, NEW JERSEY, A CORPORATION OF DELAWARE PROCESS OF TREATINGCRACKED HYDROCARBON S Application filed January 10, 1927. Serial No.160,065.

urated hydrocarbons which comprises passing the distillate in vapor formthrough a catalytic agent such as fullers earth to' convert theunsaturated constituents by polymerization into compounds of higherboiling point which-may be separated from the vaporized saturatedhydrocarbons.

According to the present invention, advantage is taken of the fact thatin the cracking of petroleum oils free hydrogen is produced. The desiredportion of the distillate of the cracking operation which includesunsaturated hydrocarbons and free hydrogen is brought into contact witha catalytic material such, for example, as fullers earth coated orimpregnated with a metallic hydrogenation catalyst, preferably nickel,or.

saturated hydrocarbons. It may be that the,

hydrogen content is insuflicient to saturate all the unsaturatedhydrocarbons present and under thesecircumstances some of theunsaturated hydrocarbons which are not hydrogenated may be polymerizedby contact with the fullers earth into compounds having higher boilingpoints than the temperature at which the hydrogenation operation iscarried on. The saturated hydrocarbons pass ofi as vapors and aresubsequently condensed. The polymers condensed in the catalyst arecollected and refluxed to the still for redistillation. This method oftreating cracked distillate produces a-higher yield of the desiredproduct than heretofore, as the hydrogenation reduces materially thevolume of the unsaturated hydrocarbons converted into polymers andincreases the volume of the saturated hydrocarbon compounds dischargedfrom the catalyst.

Other objects, novel features and advantages of-the invention will beapparent from the following specification and accompanying drawingwherein the single figure illustrates diagrammatically an apparatus fortreating hydrocarbons in accordance with the invention. 2

In the apparatus, 10 designates a cracking still which may be of anydesired type. 11 is a fractionating device of any suitable type to whichdistillate in vapor form is led from the still by means of the pipe 12.A pipe 13 is provided for refluxing from the frac tionator 11 to thestill 10 any condensate collecting in the fractionator. 14 is a treatingtower torwhich vapor from the fractiona tor is supplied through the pipe15 controlled by the valve 16. A perforated funnel-likev shelf 17 isarranged within the tower 14 and terminates in a discharge spout 18extending through the bottomof the tower 14 and controlled by the valve19. A pipe 20 leads from the treating tower 14 to a condenser 21 fromwhich a pipe 22 leads to a storage tank 23; A reflux pipe 24 leads fromthe bottom of the treating tower 14 through a valve 25 and trap 26 tothe inlet of a pump 27, the outlet of which communicates with the bottomof the fractionator- 11. This provides means for returning to the still10 for redistillation any condensate collecting in the bottom of thetower 14.

Within the tower 14 is provided a supply 28 of a catalytic material,such, for example, as fullers earth, coated or impregnated with ametallic hydrogenation catalyst, preferably nickel, or a mixture thereofwith fullers earth. This material is prevented fromesifting through theperforationsin the shelf 17 by layers of mineral woo screens, etc., ar-

distillate, which comprises free hydrogen and unsaturated hydrocarbonsalong with saturated hydrocarbons, is supplied to the frac tionator 11.After fractionation, the vapors are passed through the catalyticmaterial in the tower 14, preferably at a temperature of between 150 to225 C. when gasoline is being produced. At this temperature, the

hydrogen in the presence of the catalytic material combines withunsaturated hydrocarbons to form. saturated hydrocarbons which pass outthrough the pipe 20 in vapor form, along with the other saturatedhydrocarbons.

The free'hydrogen may be sufficient to hydroperforations and arecollected in the bot-' tom of the tower and refluxed to'the still forredistillation.

It is understood, of course, that if the process is carried on undersuper atmospheric pressure, which might be the case if the process isused in conjunction with a cracking system of the type in which thedistillate is condensed under pressure, the temperatures may run higherto an extent depending upon the pressure.

A higher yield of the desired product than heretofore obtainable isobtainable by this process without additional cost except for the costof metallizing the fuller's earth. The hydrogen produced by the crackingoperation, and which formerly has been vented as an uncondensible gas,is utilized to convert into saturated hydrocarbon compounds a portion orall of the unsaturated hydrocarbon compounds which formerly werepolymerized and refluxed for distillation. The volume of polymersrefluxed is substantially decreased and the volume of saturatedhydrocarbon compounds discharged from the catalyst in vapor form iscorrespondingly increased.

I claim:

1. The process which comprises cracking petroleum oil and subsequentlysubjecting the cracked product at approximately 200 C. and in vapor formundiluted by extraneous gases and mixed with free hydrogen producedsolely in the cracking operation, to the action of fullers earthimpregnated with a metallic hydrogenation catalyst.

0 2. The process which comprises cracking petroleum oil and subsequentlysubjecting the cracked product at approximately 200 C.

and in vapor form undiluted by extraneous gases and mixed with freehydrogen produced solely in the cracking operation, to the action offullers earth-coated witha metallic hydrogen catalyst.

3. The process of producing gasoline which comprises cracking petroleumoil, fractionating the cracked product to separate the gasoline contentand subsequently subjecting the hydrocarbons present ,to an extentdepending upon the hydrogen content andpolymerizmg a part at least ofthe remaining hydrocarbons. I

4. The process which comprises cracking petroleum oil and subsequentlysubjecting the cracked product at approximately 200 C. and in vapor formundiluted by extraneous gases and mixed with free hydrogen pro ducedsolely in the cracking operation, to the action of fullers earth coatedwith nickel.

5. The process of producing gasoline which comprises cracking petroleumoil and subsequently subjecting the cracked gasoline at approximately200 C. and in vapor form undiluted by extraneous gases and mixed withfree hydrogen produced solely in the cracking operation, to the actionof a mixture of fullers earth and fullers earth coated with nickel tohydrogenate the unsaturated hydr0- .carbons to an extent depending uponthe hydrogen content and to polymerize part at least of the remainingunsaturated hydrocarbons. A y

6. The process of producing gasoline which comprises cracking petroleumoil, fractionating the cracked productto separate gasoline from theremainder and subsequently subj ectin the cracked gasoline atapproximately 200 traneous gases and mixed with free hydrogen producedsolely in the cracking operation, to the action of fullersearth coatedwith a metallic hydrogenation catalyst.

In testimony whereof, I have signed my name to this specification.

- THOMAS -T. GRAY.

6. and in vapor form undiluted by ex-

